TheRover said:
The Phillips MANT410 amplified indoor antenna, that I got thru Wal Mart, gives me 46db Amplification with dual gain tuning controls: 45db max chls 2-13, and, 30db max chls 14-69. Thw UHF dush has 310 degree turn radius and 90 degree tilt radius.
Something that worries me as an engineer... is the apparently common misconception that, if you don't want to put up an outdoor antenna, an indoor antenna with an amplifier is just as good. It isn't.
- TV signals can be
too strong. Imagine an amplifier powered from a 9-volt battery and with a gain of 10dB. (100x the voltage) Put in 0.001 volt of signal, and it's amplified to 0.1 volt. Put in 0.1 volt of signal, and it's amplified to -- 10 volts? But it can't be, because the power supply is only 9 volts. The
relative amplitude of the signal is messed up, and that's going to kill your digital reception.
- Amplifiers will amplify
everything on the frequency. Signals, noise, and interference. If the problem with your digital reception is interference from the computer in the next room -- well, the amplifier is going to amplify the computer noise just as much as it amplifies the desired TV signal.
- Reflections - multipath - "ghosts" are a common issue in indoor-antenna reception. Signals reach your antenna via more than one route -- say, one directly from the transmitter, another by going past your antenna, bouncing off the refrigerator, and bouncing back to the antenna. Ghosts will kill digital reception. An amplifier amplifies the reflected signal just as much as it amplifies the desired signal.
I would suggest an amplified indoor antenna is likely to cause more problems than solutions when used within ten miles or so of the towers, and only rarely is it going to improve reception at any location.